Extraction of Aluminium

Q.

In the commercial electrochemical process for Aluminium extraction, the electrolyte used is:

1. $Al(OH{)}_3$ in NaOH

2. An aqueous solution of $A{l}_2(S{O}_4{)}_3$

3. A molten mixture of $A{l}_2{O}_3$ & $N{a}_{3}Al{F}_6$

4. A molten mixture of $A{l}_2{O}_3$ & $Al(OH{)}_3$

Q. Hall-Heroult process is used for the extraction of

1. $Hg$
2. $Cu$
3. $Al$
4. $Zn$

Q.

Complete the following

$2A{l}_2{O}_3+3C\to 4A+3B$. A & B are as follows.

1. CO, Al

2. Al, CO

3. Al, CO₂

4. CO₂, Al

Q.

The bauxite ore of aluminium is concentrated by froth flotation

1. False

2. True

Q.

During the electrolytic extraction of Aluminium, purified alumina is mixed with $N{a}_3$ $Al{F}_6$ and $Ca{F}_2$. Why?

1. They increase the conductivity

2. They increase the Melting point of the mix

3. They decrease the conductivity

4. They decrease the Melting Point of the mix

Q. Carbon-based reduction method is not used for the extraction of:

1. tin from $Sn{O}_2$
2. iron from $F{e}_2{O}_3$
3. aluminium from $A{l}_2{O}_3$
4. magnesium from $CaC{O}_3.MgC{O}_3$

Q.

Complete the following

$2A{l}_2{O}_3+3C\to 4A+3B$. A & B are as follows.

1. Al, CO₂

2. CO₂, Al

3. Al, CO

4. CO, Al

Q.

In the commercial electrochemical process for Aluminium extraction, the electrolyte used is:

1. $Al(OH{)}_3$ in NaOH

2. A molten mixture of $A{l}_2{O}_3$ & $N{a}_{3}Al{F}_6$

3. A molten mixture of $A{l}_2{O}_3$ & $Al(OH{)}_3$

4. An aqueous solution of $A{l}_2(S{O}_4{)}_3$

Q. In the context of the Hall-Heroult process for the extraction of Al, which of the following statements is false?

1. $CO$ and $C{O}_2$ are produced in this process

2. $A{l}_2{O}_3$ is mixed with $Ca{F}_2$, which lowers the melting point of the mixture and brings conductivity

3. $A{l}^{3+}$ is reduced at the cathode to form $Al$

4. $N{a}_{3}Al{F}_6$ serves as the electrolyte

Q.

Electrolytic reduction of alumina to aluminium by Hall-Heroult process is carried out:

1. in the presence of NaCl

2. in the presence of fluorite

3. in the presence of cryolite which forms a melt with a lower melting temperature

4. in the presence of cryolite which forms a melt with a higher melting temperature